Aiwa XR-EM52, Service Manual

Page: 51 / 73

Hz
FREQUENCY COUNTER
TP
GND
1.TAPE SPEED ADJUSTMENT
Requirements
Measuring equipments : W ow & flutter meter (frequency counter )
Test Tape: TTA-100 (3 k Hz)
Test point: C651(Lch),C652(Rch),GND
Adjustment point : Tape speed adjustment point (motor)
1) Connect Test point to the Wow & flutter meter.
2) Insert the test tape (TTA-100), play back center of the tape
and adjust the motor adjustment point until it becomes 3,000Hz +3 / -2%.
2.WOW & FLUTTER CHECK
Requirements
Test tape: TTA-100 (3 k Hz)
Test point: C651(Lch),C652(Rch),GND
1) Connect the Test point to the Wow & flutter meter.
2) Set the indicator to JIS and the mode to W RMS (WTD)
of the Wow & fl u tter meter.
3) Play back the center of the test tape (TTA-100) and check
that it is below 0.25%.
3.HEAD AZIMUTH ADJUSTMENT
Requirements
Measuring equipment: Oscilloscope
Test Tape: TTA-330 (8 k Hz)
Test point: C651(Lch),C652(Rch),GND
Adjustment point: Head azimuth screw
1) Connect the Test point to the oscilloscope of CH1 and CH2.
2) Set the V mode of the oscilloscope to ADD.
3) Insert the test tape (TTA-330) , play back the center of the tape and adjust
the head azimuth screw until the waveform of the oscilloscope has reached
the maximum when playing back at 10
k Hz.
4) After the adjustment, bond lock (1600B) the screw.
4.REC. BIAS FREQUENCY ADJUSTMENT
Requirement
Measuring equipment: F requency counter
Test point: JW38, GND
Adjustment point: L451
1) Connect the JW38 to the frequency counter.
2) Set the recording condition to the main unit.
3) Adjust the L451 until it becomes 85
k Hz+/-0.5 k Hz.
OUTPUT
OSCILLOSCOPE
Lch
Rch
CH1 CH2
Hz
WOW&FLUTTER METER
TP
%
INPUT
Hz
WOW&FLUTTER METER
TP
%
INPUT
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